1. Field of the Invention
The present invention relates to a device intended to automatically ensure the lubrication of machine shafts, especially of machines belonging to heavy service equipment and facilities.
2. Description of Background Art
The use of the device concerned permits lubrication pumps and other invention used to such end to be done without, affording additional advantages which make its installation highly appropriate on the shafts of machines subject to tough working conditions because of their functional features, and especially with respect to working temperatures, operating rates and materials involved.
A typical but not exclusive application of the automatic lubrication device which is the object of this invention is in cement plant kilns which, as known, should turn at low speed, to which end a high-power reducing gear is used, which is calculated to ensure the operation of the rotary kiln, together with a second reducing gear, commonly called a slew gear, which functions as an auxiliary gear and is mechanically connected to the high-power reducing gear. When the slew gear is driven by a motor, a large reduction takes place for driving the kiln at very low speed, as at the start of operation of the facility.
When the main reducing gear is driven by the motor, a reduction is produced at its output shaft and the kiln is driven at the rated speed. To prevent multiplication in the auxiliary reducing gear, it should be mechanically disconnected, which is usually carried out by means of a device comprising a solid shaft, a hollow shaft and a freewheel, with a motor-driven pump for lubrication of the device since, in this phase, there is no internal oil bubbling since the slew or auxiliary reducing gear is idle.
The use of the motor-driven lubrication pump poses formal and functional problems which are difficult to solve, entailing, on the one hand, a need for continuous and costly maintenance, and on the other, the risk of interruptions in lubrication, with the consequences that this entails.